5 2 exch div pstack 0.7 add 0.5 ne pstack pop 
5 1 sub pstack pop 
-1 -1 div pstack 1 5 dup -3 exch add pstack add pstack 6 exch pop pop sub pstack pop 
3 5 exch sub 1 div pstack dup sub 1 div pstack pop 
1 dup mul div sub pstack